An impressed current cathodic protection device for offshore wind turbine jacket and a method of design and installation

Abstract

This invention discloses an impressed current cathodic protection device for offshore wind turbine jacket structures, along with its design and installation method. The impressed current cathodic protection device includes a cable conduit, auxiliary anode components, and a reference electrode assembly. The cable conduit is fixedly connected to the legs of the wind turbine jacket structure. The cable conduit includes a main body and a bend section. The auxiliary anode components and the reference electrode assembly are located inside the main body. The main body is alternately composed of steel pipe grids and connecting pipes along its axial direction. Each main body contains two auxiliary anode components and one reference electrode assembly, with the reference electrode assembly located between the two auxiliary anode components. The bend section provides an entry point for the auxiliary anode components and the reference electrode assembly to enter the main body, and one end of the bend section connects to the top of the leg. The impressed current cathodic protection device of this invention is quick to install and easy to operate; it eliminates the need for personnel to dive during maintenance, resulting in a high safety factor; it provides excellent cathodic protection and corrosion resistance, which helps reduce costs.

Description

Technical Field

[0001] This invention relates to an impressed current cathodic protection device for offshore wind turbine jackets, as well as its design and installation method. Background Technology

[0002] Offshore wind power, as a major clean energy source developed by the country in recent years, boasts advantages such as large single-unit installed capacity, high effective utilization hours, and no occupation of land resources, making it one of the important strategic energy reserve methods for the nation. The steel wind turbine foundation, constructed of metal components, has a hollow inner wall. During piling, seawater and silt with high salt content remain, making it highly susceptible to corrosion due to moisture and salt spray. The outer wall, exposed to fluctuating seawater, is constantly corroded throughout its lifespan by salt spray, marine atmosphere, ocean currents, and wave splash. Currently, offshore wind turbine steel foundations commonly employ cathodic protection methods combining coatings with sacrificial anodes or impressed current. However, coatings are easily damaged by prolonged erosion from ocean currents and foreign objects, failing to provide long-term protection. Sacrificial anodes, on the other hand, suffer from significant environmental pollution, short lifespan, uncontrollable output current, and difficulty in potential detection during operation and maintenance, thus gradually being phased out of the offshore wind power cathodic protection market. Impressed current cathodic protection has advantages such as light weight, long service life, less environmental pollution, and adjustable output voltage and current, and is becoming increasingly popular.

[0003] However, the electrode structures in current offshore wind power jacket cathodic protection systems commonly employ either tensioned or fixed flange structures. For tensioned structures, such as the Chinese invention patent CN108286249A entitled "A Tensioned Impressed Current Cathodic Protection System and Its Installation Method," steel cable anchors are used for suspension. This device requires highly skilled installers and advanced tools, and during the engineering operation and maintenance phase, deep-sea diving maintenance is necessary, resulting in a high risk factor and limited application. For fixed flange structures, such as the Chinese invention patents CN113388840B entitled "A Cathodic Protection Fixing Device for Offshore Wind Power Steel Structures" and CN114182262A entitled "Anti-corrosion Device for Offshore Steel Structures and Its Control Method," workers install and fix the electrodes to the flanges of the wind turbine jacket / monoped cable conduit during the jacket manufacturing stage. Due to the weight of the electrodes, installation and cable pulling have always been difficult with this type of structure.

[0004] The electrode flange and cable conduit flange are connected via jumper cables or spot-welded bolts to achieve conductivity between the electrode and the wind turbine jacket structure. This method often results in weld corrosion before the impressed current cathodic protection system is officially put into operation due to inadequate paint protection at the spot weld points by operators, posing a significant corrosion risk. Furthermore, because flange-type electrode devices use a bolted flange structure, their service life spans the entire lifespan of the wind turbine jacket structure, exceeding 25 years, and they cannot be replaced for life. Moreover, during operation and maintenance, if paint peels off the electrode body requiring touch-up, or if marine organisms adhere to the reference electrode, manual intervention by divers is required, undoubtedly increasing maintenance risks and labor costs.

[0005] Therefore, there is an urgent need to develop an impressed current cathodic protection device suitable for offshore wind power jackets that is simple in structure, lightweight, easy to install, and easy to operate and maintain. Summary of the Invention

[0006] In view of this, in order to overcome the shortcomings of the prior art, the purpose of this invention is to provide an impressed current cathodic protection device for offshore wind turbine jackets, as well as its design and installation method. This device is quick to install and easy to operate; it does not require maintenance personnel to dive during operation and maintenance, resulting in a high safety factor; it provides good cathodic protection and corrosion resistance, which helps to reduce costs.

[0007] To achieve the above objectives, the present invention adopts the following technical solution:

[0008] One object of the present invention is to provide an impressed current cathodic protection device for offshore wind turbine jackets, comprising a cable pipe, an auxiliary anode assembly, and a reference electrode assembly. The cable pipe is fixedly connected to the legs of the wind turbine jacket. The cable pipe includes a main body and a bend section. The auxiliary anode assembly and the reference electrode assembly are located inside the main body. The main body includes multiple steel pipe grids and multiple connecting pipes, which are alternately arranged along its axial direction. Each main body contains two auxiliary anode assemblies and one reference electrode assembly, with the reference electrode assembly located between two auxiliary anode assemblies. Both the auxiliary anode assembly and the reference electrode assembly are located within the steel pipe grids of the cable pipe. The bend section provides an entrance for the auxiliary anode assembly and the reference electrode assembly to enter the main body, and one end of the bend section is connected to the top of the leg. An auxiliary anode assembly is installed on each leg of the offshore wind turbine jacket, corresponding to the splash layer and the deep water layer. The reference electrode assembly is located at the center between the two auxiliary anode assemblies. The legs of the wind turbine jacket form a backup relationship with each other. This arrangement is conducive to uniform current distribution and provides good protection for the wind turbine jacket.

[0009] By fixing the cable conduit of the impressed current cathodic protection device to the support leg of the wind turbine duct frame, the auxiliary anode assembly and reference electrode assembly are inserted into the main body of the cable conduit from the bend section. Since the inlet end of the bend section is close to the top of the support leg, and the top of the support leg and the working platform of the wind turbine duct are both above the sea surface, the structural design of the impressed current cathodic protection device of this invention allows workers to operate on the working platform when installing or dismantling the impressed current cathodic protection device without having to dive below the sea surface. This improves the safety factor of operation and maintenance and reduces manpower and material costs.

[0010] According to some preferred embodiments of the present invention, the auxiliary anode assembly includes a first sleeve and an auxiliary anode, a counterweight, and a plurality of support plates located inside the first sleeve; the sleeve wall is provided with multiple rows of first through hole units, each row of first through hole units including a plurality of spaced first through holes penetrating the thickness direction of the first sleeve.

[0011] According to some preferred embodiments of the present invention, the length of each row of the first through-hole units is less than or equal to the length of the first sleeve, the center of the first through-hole unit and the center of the first sleeve are located in the same vertical direction, and the length of the steel pipe grid is greater than the length of the first sleeve.

[0012] According to some preferred embodiments of the present invention, each of the pallets includes a support column and a plurality of extension blocks spaced apart on the outer wall of the support column. A protrusion is fixedly provided on the top surface of the extension block. The plurality of protrusions and the extension blocks form a limiting portion with respect to the support column. The side wall of the protrusions and the extension blocks away from the support column is connected to the inner wall of the first sleeve.

[0013] According to some preferred embodiments of the present invention, the support column has a groove for accommodating the counterweight along its height extension direction, the groove penetrating the top surface of the support column, and a second through hole is provided at the bottom of the support column, the second through hole communicating with the groove, the sum of the length of the second through hole and the height of the groove being equal to the height of the support column.

[0014] According to some preferred embodiments of the present invention, both ends of the auxiliary anode are provided with the support plate, the two ends of the auxiliary anode are respectively located in the limiting portion, and the anode cable of the auxiliary anode passes through a second through hole on one of the support plates near the reference electrode assembly.

[0015] According to some preferred embodiments of the present invention, the reference electrode assembly includes a second sleeve and a reference electrode, a counterweight, and a plurality of support plates located inside the second sleeve; the sleeve wall is provided with multiple rows of second through hole units, each row of second through hole units including a plurality of spaced second through holes penetrating the thickness direction of the second sleeve.

[0016] According to some preferred embodiments of the present invention, the length of each row of second through-hole units is less than or equal to the length of the second sleeve, the center of the second through-hole unit and the center of the second sleeve are located in the same vertical direction, the length of the steel pipe grid is greater than the length of the second sleeve, and the length of the second sleeve is less than the length of the first sleeve.

[0017] According to some preferred embodiments of the present invention, both ends of the reference electrode are provided with the support plate, the two ends of the reference electrode are respectively located in the limiting portion, and the measuring cable of the reference electrode passes through a second through hole on one of the support plates near one of the auxiliary anode components.

[0018] According to some preferred embodiments of the present invention, the reference electrode assembly is equidistant from the two auxiliary anode assemblies, the auxiliary anodes of the two auxiliary anode assemblies are connected by an anode cable that passes through the reference electrode assembly; the measuring cable of the reference electrode assembly is connected to the anode cable of the auxiliary anode assembly by a cable clamp.

[0019] According to some preferred embodiments of the present invention, one end of the bend is connected to the main body of the steel pipe, and the other end of the bend is provided with a sealing component. The end of the bend near the sealing component is provided with an installation hole that penetrates the pipe wall thickness direction, and the bend is provided with a cover plate corresponding to the installation hole for covering the installation hole.

[0020] According to some preferred embodiments of the present invention, the wind turbine jacket includes a working platform and a plurality of legs, the working platform being located near the top of the legs and fixedly disposed at the upper ends of the plurality of legs; an extension tube is fixedly disposed on the outer wall of the connecting pipe, and the end of the extension tube away from the connecting pipe is fixedly connected to the legs.

[0021] Another object of the present invention is to provide a design method for an impressed current cathodic protection device as described above, comprising the following steps:

[0022] Obtain the area to be protected below the average water level of the offshore wind turbine jacket, the height H of the opening on the web of the general column of the offshore wind turbine jacket, and the height of each weld on the legs of the offshore wind turbine jacket.

[0023] Calculate the diameter D and length L of the auxiliary anode assembly according to the protected area, and calculate the diameter D1 and length L1 of the reference electrode assembly according to the annual consumption rate of the reference electrode; if L > H, continue to optimize the diameter D of the auxiliary anode assembly until L < H; if L1 > H, continue to optimize the diameter D1 of the reference electrode assembly until L1 < H;

[0024] Calculate the length L2 of the steel pipe grid according to the height of each weld on the leg of the offshore wind power jacket, the length L of the auxiliary anode assembly, and the length L1 of the reference electrode assembly; L2 > L and L2 > L1;

[0025] Determine the installation positions of the auxiliary anode assembly and the reference electrode assembly inside the steel pipe main body;

[0026] Calculate the lengths and bearing capacities of the anode cable of the auxiliary anode and the measurement cable of the reference electrode assembly respectively, select the types of the anode cable and the measurement cable, and complete the design.

[0027] According to some preferred implementation aspects of the present invention, three-dimensional modeling of the offshore wind power jacket is carried out based on the structure of the offshore wind power jacket and the hydrological information of the sea area where it is located to obtain the area to be protected below the average water level of the offshore wind power jacket, the height H of the through-hole on the web of the general column of the offshore wind power jacket, and the height of each weld on the leg of the offshore wind power jacket.

[0028] According to some preferred implementation aspects of the present invention, in the step of determining the installation positions of the auxiliary anode assembly and the reference electrode assembly inside the steel pipe main body, the connection between the extension pipe fixedly arranged on the outer wall of each connecting pipe in the steel pipe main body and the leg is located between two adjacent welds.

[0029] Another object of the present invention is to provide an installation method of the impressed current cathodic protection device as described above, including the following steps:

[0030] Install the cable steel pipe on the leg during the manufacturing stage of the offshore wind power jacket, and calibrate the positions of the anode cable and the measurement cable on the cable steel pipe; put the auxiliary anode assembly and the reference electrode assembly into the cable steel pipe in sequence from the installation hole of the elbow section until both the anode cable and the measurement cable are placed at the calibrated positions, then lock and fix the anode cable and the measurement cable with the sealing component, and finally cover the through-hole on the web of the general column and the cover plate of the elbow section to complete the installation.

[0031] Due to the adoption of the above technical solutions, compared with the prior art, the beneficial effects of the present invention are as follows:

[0032] (1) The auxiliary anode assembly and reference electrode assembly inside the cable steel pipe of the impressed current cathodic protection device of the present invention are replaceable, and the on-site installation personnel can directly perform installation or disassembly operations on the working platform of the wind power duct frame without the need for personnel to go down, resulting in a high safety factor for operation and maintenance; in addition, the installation cost is low, the applicability is strong, and it is conducive to reducing manpower and material costs.

[0033] (2) The use of replaceable auxiliary anode components and reference electrode components eliminates the need for spot welding and cable bridging between the electrode body and the cable steel pipe, which helps to reduce production costs and eliminates the risk of corrosion at the weld points. This effectively solves the problem of inadequate weld point protection when the applied current is not energized before commissioning. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the main structure of the impressed current cathodic protection device in Embodiment 1 of the present invention;

[0036] Figure 2 for Figure 1 A magnified view of the structure at point A in the middle;

[0037] Figure 3 for Figure 1 A magnified view of the structure at point B in the middle;

[0038] Figure 4 This is a schematic diagram of the main structure of the impressed current cathodic protection device in Embodiment 1 of the present invention after the cable conduit is hidden;

[0039] Figure 5 This is an exploded view of the auxiliary anode assembly in Embodiment 1 of the present invention;

[0040] Figure 6 This is an exploded view of the reference electrode assembly in Embodiment 1 of the present invention;

[0041] Figure 7 This is a three-dimensional structural diagram of the tray in Embodiment 1 of the present invention;

[0042] Figure 8 This is a schematic diagram of the exploded structure of the bend section in Embodiment 1 of the present invention;

[0043] Figure 9 This is a three-dimensional structural diagram of the sealing assembly in Embodiment 1 of the present invention;

[0044] Figure 10 This is a schematic diagram of the main structure of the sealing assembly in Embodiment 1 of the present invention;

[0045] Figure 11 This is a three-dimensional structural diagram of the offshore wind turbine jacket structure in Embodiment 1 of the present invention;

[0046] Figure 12 for Figure 11 Enlarged view of the structure at points C1 and C2;

[0047] Figure 13 for Figure 11 A magnified view of the structure at point D in the middle;

[0048] The attached diagrams are labeled as follows: Wind turbine jacket - 100, support leg - 11, weld - 111, working platform - 12, support column - 13, top plate - 14, web plate - 15, opening - 151, cable conduit - 2, steel pipe grating - 21, connecting pipe - 22, bend section - 23, mounting hole - 231, cover plate - 232, sealing assembly - 24, blind flange - 241, locking gland - 242, saddle clamp - 243. Handle-244, Extension tube-25, Auxiliary anode assembly-3, First sleeve-31, First through hole-311, Auxiliary anode-32, Anode cable-33, Reference electrode assembly-4, Second sleeve-41, Third through hole-411, Reference electrode-42, Measuring cable-43, Cable clamp-44, Counterweight-5, Support plate-6, Support column-61, Groove-611, Extension block-62, Protrusion-63. Detailed Implementation

[0049] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention are clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0050] Example 1: An impressed current cathodic protection device for offshore wind turbine jacket foundations

[0051] Reference Figures 1 to 13 The present invention discloses an impressed current cathodic protection device for an offshore wind turbine jacket 100, wherein the offshore wind turbine jacket 100 includes a working platform 12, a support column 13, and multiple support legs 11, such as... Figure 11As shown, in this embodiment, the wind turbine jacket 100 has four legs 11. The upper end of the support column 13 is fixedly connected to the top of the four legs 11 via a top plate 14. The working platform 12 is fixedly installed on the upper end of the four legs 11, and the top surface of the working platform 12 is located below the top plate 14. An impressed current cathodic protection device is connected to the legs 11 of the wind turbine jacket 100, and an impressed current cathodic protection device is provided on the inner side of each leg 11.

[0052] Further, see Figures 1 to 4 The impressed current cathodic protection device includes a cable conduit 2, an auxiliary anode assembly 3, and a reference electrode assembly 4. The cable conduit 2 comprises a main body and a bend 23. Both the auxiliary anode assembly 3 and the reference electrode assembly 4 are located inside the main body. Specifically, the main body includes multiple steel pipe grids 21 and multiple connecting pipes 22. The length of the steel pipe grids 21 is greater than the length of the connecting pipes 22. The steel pipe body is alternately arranged with steel pipe grids 21 and connecting pipes 22 along its axial direction, ensuring normal operation even when the auxiliary anode assembly 3 and the reference electrode assembly 4 are not placed at the end of the main body. An extension pipe 25 perpendicular to the outer wall of the connecting pipe 22 is fixedly provided. The end of the extension pipe 25 away from the connecting pipe 22 is welded to the outer wall of the support leg 11 through a welding plate to fix the entire cable steel pipe 2 to the support leg 11. In order to avoid interference between the welding plate and the weld 111 of the support leg 11 itself (each support leg 11 is welded from multiple shorter steel pipes, so a weld 111 will be generated between two adjacent steel pipes), it is necessary to ensure that the connection point (welding plate) between the extension pipe 25 fixedly provided on the outer wall of each connecting pipe 22 in the steel pipe body and the support leg 11 is located between two welds 111 adjacent to the welding plate.

[0053] like Figure 2 and Figure 3 As shown, the steel pipe grating 21 includes multiple spaced steel bars along its radial direction, with gaps between adjacent steel bars; the bent pipe section 23 provides an inlet for the auxiliary anode assembly 3 and the reference electrode assembly 4 to enter the steel pipe body, one end of the bent pipe section 23 is fixedly connected to the steel pipe body, and the other end is connected to the top of the support leg 11; and a connecting flange and a sealing assembly 24 that mates with the connecting flange are provided at the end of the bent pipe section 23 away from the steel pipe body. See also Figure 8 The end of the bend section 23 near the sealing assembly 24 is also provided with a mounting hole 231 that penetrates the thickness of its pipe wall. When installing and removing the auxiliary anode assembly 3 and the reference electrode assembly 4, the corresponding operations are performed through the mounting hole 231. The bend section 23 is also provided with a cover plate 232 corresponding to the mounting hole 231 to cover the mounting hole 231, so as to ensure the sealing of the impressed current cathodic protection device.

[0054] Further, see Figure 4Each steel pipe body contains two auxiliary anode components 3 and one reference electrode component 4. Both the auxiliary anode components 3 and the reference electrode component 4 are located within the steel pipe grid 21 of the cable steel pipe 2, with the reference electrode component 4 positioned between the two auxiliary anode components 3. The distances from the reference electrode component 4 to each of the two auxiliary anode components 3 are equidistant. For details, see... Figures 11 to 13 An auxiliary anode assembly 3 is installed on each leg 11 of the wind turbine jacket 100 at the splash layer and deep water layer corresponding to the seawater, which helps to solve the problem of uneven protection current due to the large depth span of the jacket. The reference electrode assembly 4 is located at the center between the two auxiliary anode assemblies 3. The potential measurement accuracy of the reference electrode 42 at this position is high, and it can provide comprehensive feedback on the protection status of the entire jacket. Furthermore, the end of the auxiliary anode assembly 3 located in the deep water layer abuts against the end of the steel pipe body. The legs 11 of the wind turbine jacket 100 form a backup relationship with each other. This arrangement is conducive to uniform current distribution and provides good protection for the wind turbine jacket 100. The steel pipe grating 21 can guide the auxiliary anode assembly 3 and the reference electrode assembly 4 during placement to prevent them from shifting position under the impact of seawater flow. In addition, the hollow structure of the steel pipe grating 21 facilitates the current dissipation of the auxiliary anode 32 and the potential measurement of the reference electrode 42. It can also prevent sediment from accumulating at the end of the steel pipe body and affecting the placement of the auxiliary anode assembly 3 and the reference electrode assembly 4.

[0055] Specifically, such as Figure 5 As shown, each auxiliary anode assembly 3 includes a first sleeve 31 and an auxiliary anode 32, a counterweight 5, and multiple support plates 6 located inside the first sleeve 31; as Figure 6As shown, the reference electrode assembly 4 includes a second sleeve 41 and a reference electrode 42, a counterweight 5, and multiple support plates 6 located inside the second sleeve 41. The length of the steel pipe grid 21 is greater than the length of the first sleeve 31, and the length of the first sleeve 31 is greater than the length of the second sleeve 41. The first sleeve 31 has multiple rows of first through-hole units on its wall. Each row of first through-hole units includes multiple evenly spaced first through-holes 311 penetrating the thickness direction of the first sleeve 31 wall. In this embodiment, the length of each row of first through-hole units is less than the length of the first sleeve 31, and the center of the first through-hole unit is located in the same vertical direction as the center of the first sleeve 31. The arrangement of the first through-holes 311 on the first sleeve 31 facilitates current dissipation and protects the anode surface coating from damage. Furthermore, the second sleeve 41 has multiple rows of third through-hole units on its cylinder wall. Each row of third through-hole units includes multiple spaced third through-holes 411 that penetrate the thickness direction of the second sleeve 41 cylinder wall. In this embodiment, the length of each row of third through-hole units is less than the length of the second sleeve 41, and the center of the third through-hole unit is located in the same vertical direction as the center of the second sleeve 41. The arrangement of the third through-holes 411 on the second sleeve 41 facilitates the reference electrode 42 in acquiring potential.

[0056] Furthermore, such as Figure 7 As shown, in this embodiment, each support plate 6 includes a support column 61 and three extension blocks 62 evenly spaced on the outer wall of the support column 61. A protrusion 63 is fixedly provided on the top surface of each extension block 62 away from the support column 61. The three protrusions 63 and the extension blocks 62 form a limiting portion with the support column 61. The support column 61 has a groove 611 extending along its height direction to accommodate the counterweight 5, and this groove 611 penetrates the top surface of the support column 61. A second through hole communicating with the groove 611 is also provided at the bottom of the support column 61. The sum of the length of the second through hole and the height of the groove 611 is equal to the height of the support column 61. The second through hole facilitates the passage of the anode cable 33 of the auxiliary anode 32 and the measuring cable 43 of the reference electrode 42 through the support plate 6. Specifically, for the auxiliary anode assembly 3, three support plates 6 are provided. The protrusions 63 and extension blocks 62 of each support plate 6 are bonded to the inner wall of the first sleeve 31 with adhesive at the side wall away from the support column 61. A support plate 6 is located inside the first sleeve 31 at the end furthest from the reference electrode assembly 4. A counterweight 5 is placed in the groove 611 of the support plate 6 to increase the weight of the auxiliary anode assembly 3 to achieve anti-buoyancy. Additionally, support plates 6 are provided at both ends of the auxiliary anode 32, and each end of the auxiliary anode 32 is located in a corresponding limiting portion of the support plate 6 to fix the auxiliary anode 32. A support plate 6 located at the end of the auxiliary anode 32 near the counterweight 5 abuts against the support plate 6 that houses the counterweight 5. In this embodiment, as... Figure 4As shown, the auxiliary anodes 32 of the two auxiliary anode assemblies 3 share a single anode cable 33. This anode cable 33 connects to the auxiliary anode 32 in one auxiliary anode assembly 3 located away from the bend section 23, passes through a second through-hole on a support plate 6 near the reference electrode assembly 4, passes through the entire reference electrode assembly 4, and connects to one end of the auxiliary anode 32 in the other auxiliary anode assembly 3. It then extends outward from the other end of the auxiliary anode 32 in the other auxiliary anode assembly 3, passes through a second through-hole on a support plate 6 containing a counterweight 5, and continues outward until it is fixedly connected to the sealing assembly 24 at the end of the bend section 23. In this embodiment, the anode cable 33 is a tensile-resistant and seawater-resistant cable with embedded steel wire.

[0057] like Figure 6 As shown, the reference electrode assembly 4 is also provided with three support plates 6. The protrusions 63 and extension blocks 62 of each support plate 6 are bonded to the inner wall of the second sleeve 41 with adhesive. One of the support plates 6 is located inside the second sleeve 41 at the end away from the bend section 23. A counterweight 5 is placed in the groove 611 of this support plate 6 to increase the weight of the reference electrode assembly 4 to achieve anti-buoyancy. In addition, support plates 6 are provided at both ends of the reference electrode 42, and the two ends of the reference electrode 42 are respectively located in the limiting part of a corresponding support plate 6 to fix the reference electrode 42. The support plate 6 at the end of the reference electrode 42 near the counterweight 5 abuts against the support plate 6 that houses the counterweight 5. In this embodiment, as shown... Figure 4 As shown, the measuring cable 43 of the reference electrode 42 is connected to the end of the reference electrode 42 away from the counterweight 5, and extends outward from that end. The other end of the measuring cable 43 passes through a second through hole on a support plate 6 near the bend section 23 in the reference electrode assembly 4, extends outward to the second sleeve 41, and is bound and fixed to the anode cable 33 of the auxiliary anode 32 by a cable clamp 44 to realize the junction of the two cables. In this embodiment, the measuring cable 43 is a seawater-resistant cable with a shielding layer.

[0058] Furthermore, such as Figure 9 and Figure 10As shown in the figure, the sealing assembly 24 includes a blind flange 241, a locking gland 242 provided on the blind flange 241, a saddle clamp 243 and a handle 244. The saddle clamp 243 is located on one side of the blind flange 241 close to the elbow section 23, and the handle 244 is located on one side of the blind flange 241 away from the elbow section 23. The sealing assembly 24 cooperates with the connecting flange at one end of the elbow section 23 to lock and fix the anode cable 33 and the measurement cable 43. Specifically, after the measurement cable 43 and the anode cable 33 are tied and fixed by a cable clamp 44, they are tied to the saddle clamp 243 for preliminary fixation; then the blind flange 241 and the connecting flange at one end of the elbow section 23 are locked by the locking gland 242, and finally the locking and fixation of the anode cable 33 and the measurement cable 43 are completed.

[0059] Embodiment 2 Design method of impressed current cathodic protection device for offshore wind turbine jacket

[0060] The design method of the impressed current cathodic protection device for the offshore wind turbine jacket 100 of the present invention includes the following steps:

[0061] Perform three-dimensional modeling on the offshore wind turbine jacket 100 based on the structure of the offshore wind turbine jacket 100 and the hydrological information of the sea area where it is located, so as to obtain the area to be protected below the average water level of the offshore wind turbine jacket 100, the height H of the through hole 151 opened on the web 15 of the general column 13 of the offshore wind turbine jacket 100, and the height of each weld 111 on the leg 11 of the offshore wind turbine jacket 100.

[0062] Calculate the diameter D and length L of the auxiliary anode assembly 3 according to the protection area; calculate the diameter D1 and length L1 of the reference electrode assembly 4 according to the annual consumption rate of the reference electrode 42 and the design total index. If L > H, continue to optimize the diameter D of the auxiliary anode assembly 3 until L < H; if L1 > H, continue to optimize the diameter D1 of the reference electrode assembly 4 until L1 < H.

[0063] According to the height of each weld 111 on the leg 11 of the offshore wind turbine jacket 100, and in combination with the calculated length L of the auxiliary anode assembly 3 and the length L1 of the reference electrode assembly 4, design the length L2 of the steel pipe grid 21 to ensure that L2 > L and L2 > L1.

[0064] Determine the optimal installation positions of the auxiliary anode assembly 3 and the reference electrode assembly 4 inside the steel pipe main body through numerical simulation software, and optimize the simulation calculation results, optimize the distance between the steel pipe grid 21 and the connecting pipe 22, so that the connection point (welding cover plate) of the extension pipe 25 fixedly provided on the outer wall of each connecting pipe 22 in the steel pipe main body and the leg 11 is located between two adjacent welds 111 of the welding cover plate, avoiding interference between the welding cover plate and the weld 111.

[0065] Based on the installation positions of the auxiliary anode assembly 3 and the reference electrode assembly 4, as well as the diameter D and length L of the auxiliary anode assembly 3 and the diameter D1 and length L1 of the reference electrode assembly 4, the length and load-bearing capacity of the anode cable 33 of the auxiliary anode 32 and the measuring cable 43 of the reference electrode assembly 4 are calculated respectively, so as to select the anode cable 33 and the measuring cable 43 and complete the design.

[0066] Example 3: Installation method of impressed current cathodic protection device for offshore wind turbine jacket foundation

[0067] An impressed current cathodic protection device for an offshore wind turbine jacket 100 of the present invention is installed by the following method, so that the impressed current cathodic protection device is installed on the inner side of the corresponding support leg 11 of the wind turbine jacket 100. The installation method specifically includes the following steps:

[0068] The jacket manufacturer completes the fabrication of cable steel pipe 2 during the jacket manufacturing stage according to the above design results. The cathodic protection system supplier completes the fabrication and assembly of auxiliary anode assembly 3, reference electrode assembly 4, anode cable 33, and measuring cable 43 according to the above design results. The position calibration of anode cable 33 and measuring cable 43 is completed based on the optimal installation position of auxiliary anode assembly 3 and reference electrode assembly 4 obtained by simulation calculation.

[0069] The installer opens the cover plate 232 of the bend section 23 and inserts the auxiliary anode assembly 3 and the reference electrode assembly 4 into the steel pipe body in the design sequence through the mounting holes 231 on the bend section 23. According to the marked positions of the anode cable 33 and the measuring cable 43, when the anode cable 33 and the measuring cable 43 are placed in the marked positions, it means that the auxiliary anode assembly 3 and the reference electrode assembly 4 have also been placed in the designated positions.

[0070] The ends of the anode cable 33 and the measuring cable 43 are pulled out by the traction rope, and the anode cable 33 and the measuring cable 43 are locked and fixed by the saddle buckle 243 and the locking gland 242 on the blind flange 241.

[0071] Finally, a multi-layered petrolatum coating material is used to cover the opening 151 on the web plate 15 of the general column 13 and the cover plate 232 covering the mounting hole 231 on the bend section 23, so as to protect the cover plate 232 from corrosion and complete the installation of the impressed current cathodic protection device.

[0072] The auxiliary anode assembly and reference electrode assembly inside the cable conduit of the impressed current cathodic protection device of this invention are replaceable. On-site installation personnel can directly perform installation or disassembly operations on the working platform of the wind turbine duct frame without the need for personnel to descend into the ground, resulting in a high safety factor for operation and maintenance. Furthermore, it has low installation costs, strong versatility, and helps reduce labor and material costs. The use of replaceable auxiliary anode and reference electrode assemblies eliminates the need for spot welding and cable bridging between the electrode body and the cable conduit, reducing production costs and eliminating the risk of weld corrosion. This effectively solves the problem of inadequate weld protection before energization of the impressed current.

[0073] The above embodiments are only for illustrating the technical concept and features of the present invention, and are intended to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made in accordance with the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. An impressed current cathodic protection device for offshore wind turbine jackets, characterized in that, The system includes a cable conduit, auxiliary anode components, and a reference electrode component. The cable conduit is fixedly connected to the legs of the wind turbine conductor frame. The cable conduit includes a main body and a bend. The auxiliary anode components and the reference electrode component are located inside the main body. The main body includes multiple steel pipe grids and multiple connecting pipes, which are alternately arranged along its axial direction. Each main body contains two auxiliary anode components and one reference electrode component, with the reference electrode component located between two auxiliary anode components. Both the auxiliary anode components and the reference electrode component are located within the steel pipe grids of the cable conduit. The bend provides an entrance for the auxiliary anode components and the reference electrode component to enter the main body, and one end of the bend is connected to the top of the leg. The auxiliary anode assembly includes a first sleeve and an auxiliary anode, a counterweight, and multiple support plates located inside the first sleeve. The sleeve wall is provided with multiple rows of first through hole units, each row of first through hole units including multiple spaced first through holes penetrating the thickness direction of the first sleeve. Each support plate includes a support column and multiple extension blocks spaced on the outer wall of the support column. The top surface of the extension block is fixedly provided with a protrusion, and the multiple protrusions and the extension blocks form a limiting part with the support column. The side wall of the protrusions and extension blocks away from the support column is connected to the inner wall of the first sleeve.

2. The impressed current cathodic protection device according to claim 1, characterized in that, The length of the first through-hole unit in each row is less than or equal to the length of the first sleeve, the center of the first through-hole unit and the center of the first sleeve are located in the same vertical direction, and the length of the steel pipe grid is greater than the length of the first sleeve.

3. The impressed current cathodic protection device according to claim 1, characterized in that, The support column has a groove for accommodating the counterweight along its height extension direction. The groove penetrates the top surface of the support column. The bottom of the support column has a second through hole that communicates with the groove. The sum of the length of the second through hole and the height of the groove is equal to the height of the support column.

4. The impressed current cathodic protection device according to claim 3, characterized in that, The auxiliary anode is provided with a support plate at both ends, and the two ends of the auxiliary anode are respectively located in the limiting part. The anode cable of the auxiliary anode passes through a second through hole on one of the support plates near the reference electrode assembly.

5. The impressed current cathodic protection device according to claim 4, characterized in that, The reference electrode assembly includes a second sleeve and a reference electrode, a counterweight, and multiple support plates located inside the second sleeve; the cylinder wall of the second sleeve is provided with multiple rows of third through hole units, and each row of the third through hole units includes multiple spaced third through holes that penetrate the thickness direction of the second sleeve.

6. The impressed current cathodic protection device according to claim 5, characterized in that, The length of each row of the third through-hole unit is less than or equal to the length of the second sleeve. The center of the third through-hole unit and the center of the second sleeve are located in the same vertical direction. The length of the steel pipe grid is greater than the length of the second sleeve, and the length of the second sleeve is less than the length of the first sleeve.

7. The impressed current cathodic protection device according to claim 6, characterized in that, Both ends of the reference electrode are provided with the support plates, both ends of the reference electrode are respectively located in the limiting parts, and the measuring cable of the reference electrode passes through a second through hole on one of the support plates close to one of the auxiliary anode assemblies.

8. The impressed current cathodic protection device according to claim 7, characterized in that, The distances from the reference electrode assembly to the two auxiliary anode assemblies are equal, and the auxiliary anodes of the two auxiliary anode assemblies are connected by an anode cable, and the anode cable penetrates through the reference electrode assembly; The measuring cable of the reference electrode assembly is connected to the anode cable of the auxiliary anode assembly through a cable clamp.

9. The impressed current cathodic protection device according to claim 1, characterized in that, One end of the elbow section is connected to the steel pipe body, a sealing assembly is arranged at the other end of the elbow section, an installation hole penetrating in the thickness direction of the pipe wall is opened at the end of the elbow section close to the sealing assembly, and a cover plate for covering the installation hole is arranged corresponding to the installation hole on the elbow section.

10. The impressed current cathodic protection device according to claim 1, characterized in that, The offshore wind power jacket includes a working platform and a plurality of legs, the working platform is close to the top of the legs, and the working platform is fixedly arranged at the upper ends of the plurality of legs; an extension pipe is fixedly arranged on the outer wall of the connecting pipe, and one end of the extension pipe far away from the connecting pipe is fixedly connected to the leg.

11. A design method for an impressed current cathodic protection device as described in any one of claims 1 to 10, characterized in that, The following steps are included: Obtain the area to be protected below the average water level of the offshore wind power jacket, the height H of the opening on the web of the general column of the offshore wind power jacket, and the heights of each weld on the legs of the offshore wind power jacket; Calculate the diameter D and length L of the auxiliary anode assembly according to the protection area, and calculate the diameter D1 and length L1 of the reference electrode assembly according to the annual consumption rate of the reference electrode; if L > H, continue to optimize the diameter D of the auxiliary anode assembly until L < H; if L1 > H, continue to optimize the diameter D1 of the reference electrode assembly until L1 < H; Calculate the length L2 of the steel pipe grid according to the heights of each weld on the legs of the offshore wind power jacket, the length L of the auxiliary anode assembly, and the length L1 of the reference electrode assembly; L2 > L and L2 > L1; Determine the installation positions of the auxiliary anode assembly and the reference electrode assembly inside the steel pipe body; Respectively calculate the lengths and bearing capacities of the anode cable of the auxiliary anode and the measuring cable of the reference electrode assembly, select the types of the anode cable and the measuring cable, and complete the design.

12. The design method according to claim 11, characterized in that, Perform three-dimensional modeling on the offshore wind power jacket through the structure of the offshore wind power jacket and the hydrological information of the sea area where it is located to obtain the area to be protected below the average water level of the offshore wind power jacket, the height H of the opening on the web of the general column of the offshore wind power jacket, and the heights of each weld on the legs of the offshore wind power jacket.

13. The design method according to claim 11, characterized in that, In the step of determining the installation positions of the auxiliary anode assembly and the reference electrode assembly inside the steel pipe body, the connection part between the extension pipe fixedly arranged on the outer wall of each connecting pipe in the steel pipe body and the leg is located between two adjacent welds.

14. A method for installing an impressed current cathodic protection device as described in any one of claims 1 to 10, characterized in that, The following steps are included: During the manufacturing stage of offshore wind turbine jacket, cable steel pipes are installed on the legs, and the positions of anode cables and measuring cables are marked on the cable steel pipes. Auxiliary anode components and reference electrode components are sequentially placed into the cable steel pipes through the mounting holes of the bend section until the anode cables and measuring cables are all placed in the marked positions. Then, the anode cables and measuring cables are locked and fixed to the sealing components. Finally, the openings on the web of the general column and the cover plates of the bend section are covered to complete the installation.

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